JP2024111555A - Liquid crystal polyester composition, film, laminate and method for producing same - Google Patents

Abstract

A liquid crystal polyester composition having excellent adhesive strength with a metal layer is provided.
[Solution] A liquid crystal polyester composition containing a liquid crystal polyester (A) and at least one thermoplastic resin selected from the group consisting of a thermoplastic polyimide and an aromatic polysulfone, wherein the liquid crystal polyester (A) has a repeating unit derived from an aromatic hydroxylamine or a repeating unit derived from an aromatic diamine.
[Selection diagram] None

Description

The present invention relates to a liquid crystal polyester composition, a film, and a laminate, and a method for producing the same.

Liquid crystal polyesters are known to have high chemical stability, heat resistance and dimensional accuracy, and are used in a variety of fields, including electrical, electronic, mechanical, optical equipment, automotive, aircraft and medical fields. Among these fields, liquid crystal polyesters have attracted particular attention as a material for electronic components, due to their low dielectric loss and excellent electrical properties.

Patent Document 1 describes a method for producing a liquid crystalline polyester film laminate in which a liquid crystalline polyester film and a metal layer are laminated together, in which a solution of a liquid crystalline polyester containing 10 to 35 mol % of at least one structural unit selected from the group consisting of structural units derived from aromatic diamines, structural units derived from aromatic amines having phenolic hydroxyl groups, and structural units derived from aromatic amino acids is cast into a film, and the solvent is then removed to obtain the liquid crystalline polyester film.

Patent No. 4479355

However, there is still room for improvement in technology to improve the adhesion strength between the metal layer and the film containing liquid crystal polyester.

The present invention has been made to solve the above problems, and aims to provide a liquid crystal polyester composition capable of producing a film having excellent adhesive strength with a metal layer, a film, and a laminate, and a method for producing the same.

Means for Solving the Problems The present inventors conducted intensive research to solve the above problems and discovered that a film containing a liquid crystal polyester and at least one thermoplastic resin selected from the group consisting of a thermoplastic polyimide and an aromatic polysulfone has excellent adhesion strength to a metal layer, thereby completing the present invention.
That is, the present invention has the following aspects.

（式中、Ｒ_１は少なくとも１つの脂環式炭化水素構造を含む炭素数６～２２の２価の基である。Ｒ_２は炭素数５～１６の２価の鎖状脂肪族基である。Ｘ_１及びＸ_２は、それぞれ独立に、少なくとも１つの芳香環を含む炭素数６～２２の４価の基である。）
＜１０＞ 前記熱可塑性ポリイミドの、前記式（Ｉ）の繰返し単位と前記式（ＩＩ）の繰返し単位との合計１００モル％に対する、前記式（Ｉ）の繰返し単位の含有割合が２０モル％以上７０モル％以下である、前記＜９＞に記載の液晶ポリエステル組成物。
＜１１＞ 液晶ポリエステル（Ａ）と、
熱可塑性ポリイミド及び芳香族ポリスルホンからなる群から選択される少なくとも一種の熱可塑性樹脂と、
前記液晶ポリエステル（Ａ）を可溶な溶媒と、を含有する、液晶ポリエステル組成物。
＜１２＞ 液晶ポリエステル（Ａ）と、
熱可塑性ポリイミド及び芳香族ポリスルホンからなる群から選択される少なくとも一種の熱可塑性樹脂と、を含有し、
前記液晶ポリエステル（Ａ）が、芳香族ヒドロキシルアミンに由来する繰返し単位、又は芳香族ジアミンに由来する繰返し単位を有する、フィルム。
＜１３＞ 金属層と、前記金属層上に積層された前記＜１２＞に記載のフィルムと、を備える積層体。
＜１４＞ 金属層上に、前記＜１＞～＜１１＞のいずれか一つに記載の液晶ポリエステル組成物を塗布し、前記金属層上にフィルムを形成することを含む、前記＜１３＞に記載の積層体の製造方法。 <1> A liquid crystal polyester (A),
At least one thermoplastic resin selected from the group consisting of thermoplastic polyimide and aromatic polysulfone;
The liquid crystal polyester composition, wherein the liquid crystal polyester (A) has a repeating unit derived from an aromatic hydroxylamine or a repeating unit derived from an aromatic diamine.
<2> The liquid crystal polyester composition according to <1>, wherein the liquid crystal polyester (A) has a repeating unit represented by the following formula (A1), a repeating unit represented by the following formula (A2), and a repeating unit represented by the following formula (A3).
(A1)-O-Ar ¹ -CO-
(A2) -CO-Ar ² -CO-
(A3)-X-Ar ³ -Y-
(Wherein,
Ar ¹ represents a 1,4-phenylene group, a 2,6-naphthylene group, or a 4,4′-biphenylene group;
^Ar2 represents a 1,4-phenylene group, a 1,3-phenylene group, or a 2,6-naphthylene group;
^Ar3 represents a 1,4-phenylene group or a 1,3-phenylene group;
X represents --NH--, and Y represents --O-- or --NH--.
The hydrogen atoms in the groups represented by Ar ¹ , Ar ² and Ar ³ may each independently be substituted with a halogen atom, an alkyl group or an aryl group.
<3> Further, the liquid crystal polyester composition contains liquid crystal polyester particles including a liquid crystal polyester (B),
The liquid crystal polyester composition according to <1> or <2>, wherein the liquid crystal polyester (B) does not have a repeating unit derived from an aromatic hydroxylamine and a repeating unit derived from an aromatic diamine.
<4> The liquid crystal polyester composition according to <3>, wherein the content of the liquid crystal polyester particles is 5% by mass or more and 80% by mass or less with respect to 100% by mass of a total content of solids contained in the liquid crystal polyester composition.
<5> The liquid crystal polyester composition according to any one of <1> to <4>, wherein the content of the thermoplastic resin is 1 part by mass or more relative to 100 parts by mass of the liquid crystal polyester (A).
<6> The liquid crystal polyester composition according to any one of <1> to <5>, wherein the content of the liquid crystal polyester (A) in the liquid crystal polyester composition is 10% by mass or more and 90% by mass or less, based on 100% by mass of a total content of solids contained in the liquid crystal polyester composition.
<7> The liquid crystal polyester composition according to any one of <1> to <6>, further comprising a solvent capable of dissolving the liquid crystal polyester (A).
<8> The liquid crystal polyester composition according to any one of <1> to <7>, wherein the thermoplastic resin is a thermoplastic polyimide.
<9> The liquid crystal polyester composition according to <8>, wherein the thermoplastic polyimide has a repeating unit represented by the following formula (I) and a repeating unit represented by the following formula (II):

(In the formula, R ₁ is a divalent group having 6 to 22 carbon atoms containing at least one alicyclic hydrocarbon structure. R ₂ is a divalent chain aliphatic group having 5 to 16 carbon atoms. X ₁ and X ₂ are each independently a tetravalent group having 6 to 22 carbon atoms containing at least one aromatic ring.)
<10> The liquid crystal polyester composition according to <9>, wherein the content of the repeating unit of the formula (I) is 20 mol % or more and 70 mol % or less with respect to a total of 100 mol % of the repeating unit of the formula (I) and the repeating unit of the formula (II).
<11> A liquid crystal polyester (A),
At least one thermoplastic resin selected from the group consisting of thermoplastic polyimide and aromatic polysulfone;
A liquid crystal polyester composition comprising: a liquid crystal polyester (A) and a solvent capable of dissolving the liquid crystal polyester (A).
<12> A liquid crystal polyester (A),
At least one thermoplastic resin selected from the group consisting of thermoplastic polyimide and aromatic polysulfone;
The liquid crystal polyester (A) has a repeating unit derived from an aromatic hydroxylamine or a repeating unit derived from an aromatic diamine.
<13> A laminate comprising: a metal layer; and the film according to <12> laminated on the metal layer.
<14> A method for producing the laminate according to <13>, comprising applying the liquid crystal polyester composition according to any one of <1> to <11> onto a metal layer to form a film on the metal layer.

According to the present invention, there can be provided a liquid crystal polyester composition which contains a liquid crystal polyester and can be used to produce a film having excellent adhesive strength with a metal layer.
Furthermore, according to the present invention, a film having excellent adhesive strength with a metal layer can be provided.
Furthermore, according to the present invention, it is possible to provide a laminate comprising a metal layer and a film, and having excellent adhesive strength with the metal layer.

FIG. 1 is a cross-sectional view showing a configuration of a film according to one embodiment of the present invention. 1 is a cross-sectional view showing a configuration of a laminate according to one embodiment of the present invention. 1 is a schematic diagram showing a process for producing a film and a laminate according to one embodiment of the present invention. 1 is a schematic diagram showing a process for producing a film and a laminate according to one embodiment of the present invention. 1 is a schematic diagram showing a process for producing a film and a laminate according to one embodiment of the present invention. 1 is a schematic diagram showing a manufacturing process of a film according to one embodiment of the present invention.

The following describes embodiments of the liquid crystal polyester composition, film, and laminate of the present invention and the method for producing the same.

<Liquid crystal polyester composition>
The liquid crystal polyester composition of the embodiment contains a liquid crystal polyester (A) and at least one thermoplastic resin selected from the group consisting of a thermoplastic polyimide and an aromatic polysulfone, and the liquid crystal polyester (A) has a repeating unit derived from an aromatic hydroxylamine or a repeating unit derived from an aromatic diamine.

The liquid crystal polyester composition of the embodiment contains a liquid crystal polyester and at least one thermoplastic resin selected from the group consisting of thermoplastic polyimide and aromatic polysulfone, and when laminated with a metal layer as a film, the adhesive strength with the metal layer is improved compared to a case where the thermoplastic resin is not contained.

In the liquid crystal polyester composition, the content of the thermoplastic resin relative to 100 parts by mass of the liquid crystal polyester (A) is preferably 1 part by mass or more, more preferably 3 parts by mass or more, and even more preferably 5 parts by mass or more.
A liquid crystal polyester composition containing a thermoplastic resin in an amount equal to or greater than the above upper limit is more effective in improving the adhesive strength with a metal layer.

In the liquid crystal polyester composition, the content of the thermoplastic resin relative to 100 parts by mass of the liquid crystal polyester (A) is preferably 80 parts by mass or less, more preferably 70 parts by mass or less, and even more preferably 65 parts by mass or less.
A liquid crystal polyester composition containing a thermoplastic resin in an amount not greater than the above upper limit is more effective in improving the adhesive strength with a metal layer.

In the liquid crystal polyester composition, the content of the thermoplastic resin relative to 100 parts by mass of the liquid crystal polyester (A) may be, for example, in the range of values from 1 part by mass to 80 parts by mass, from 3 parts by mass to 70 parts by mass, or from 5 parts by mass to 65 parts by mass.

In addition, since the liquid crystal polyester (A) has a repeating unit derived from an aromatic hydroxylamine or a repeating unit derived from an aromatic diamine, it has good solubility in a solvent described below. In addition, when the liquid crystal polyester (A) is laminated with a metal layer as a film, the adhesive strength with the metal layer is also improved.

The liquid crystal polyester (A) may contain an amide bond or a repeating unit having an imino group (-NH-).

The liquid crystal polyester (A) may be soluble in the solvent described below.

The solubility of liquid crystal polyester in a solvent can be confirmed by carrying out the following test.

Test method: 5 parts by mass of liquid crystal polyester is stirred in 95 parts by mass of solvent at 180°C with an anchor blade at 200 rpm for 6 hours, then cooled to room temperature. Then, the mixture is filtered using a membrane filter with a mesh size of 5 μm and a pressure filter, and the residue on the membrane filter is checked. If no residue is found, the mixture is judged to be soluble in the solvent.

The liquid crystal polyester composition of the embodiment can contain the liquid crystal polyester (A), the thermoplastic resin, and optional components that may be contained as necessary, such that the total content (mass%) of those components in the liquid crystal polyester composition does not exceed the total mass (100 mass%) of the liquid crystal polyester composition of the embodiment.

<Liquid Crystal Polyester (A)>
The liquid crystal polyester is a liquid crystal polyester that exhibits liquid crystallinity in a molten state, and is preferably one that melts at a temperature of 450° C. or less.

The liquid crystal polyester is preferably a wholly aromatic liquid crystal polyester having only repeating units derived from aromatic compounds.

In this specification, "derived" means that in the polymerization of the raw material monomer, the chemical structure of the functional group that contributes to the polymerization changes, but other chemical structures do not change. The concept of origin here also includes cases where the origin is a polymerizable derivative of the raw material monomer.

Examples of polymerizable derivatives of compounds having a carboxyl group, such as aromatic hydroxycarboxylic acids and aromatic dicarboxylic acids, include esters in which the carboxyl group has been converted to an alkoxycarbonyl group or an aryloxycarbonyl group; acid halides in which the carboxyl group has been converted to a haloformyl group; and acid anhydrides in which the carboxyl group has been converted to an acyloxycarbonyl group.

Examples of polymerizable derivatives of compounds having a hydroxyl group, such as aromatic hydroxycarboxylic acids, aromatic diols and aromatic hydroxyamines, include acylation products in which the hydroxyl group is acylated to convert it into an acyloxyl group.
Examples of polymerizable derivatives of compounds having an amino group, such as aromatic hydroxyamines and aromatic diamines, include acylated products in which the amino group is acylated to convert it into an acylamino group.

The liquid crystal polyester (A) has a repeating unit derived from an aromatic hydroxylamine or a repeating unit derived from an aromatic diamine.

An example of a liquid crystal polyester (A) having a repeating unit derived from an aromatic hydroxylamine or a repeating unit derived from an aromatic diamine is a liquid crystal polyester having a repeating unit represented by the following formula (A1), a repeating unit represented by the following formula (A2), and a repeating unit represented by the following formula (A3).

(A1) -O-Ar ¹ -CO-
(A2) -CO-Ar ² -CO-
(A3) -X-Ar ³ -Y-
(In the formula, Ar ¹ represents a 1,4-phenylene group, a 2,6-naphthylene group, or a 4,4'-biphenylene group, and Ar ² represents a 1,4-phenylene group, a 1,3-phenylene group, or a 2,6-naphthylene group; Ar ³ represents a 1,4-phenylene group or a 1,3-phenylene group; X represents -NH-; and Y represents -O- or -NH-. The hydrogen atoms in the groups represented by Ar ¹ , Ar ² and Ar ³ may each be independently substituted with a halogen atom, an alkyl group or an aryl group.

Examples of the halogen atom which can substitute for a hydrogen atom in Ar ¹ , Ar ² or Ar ³ include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom.

Examples of the alkyl group which can substitute for a hydrogen atom in Ar ¹ , Ar ² , or Ar ³ include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a s-butyl group, a t-butyl group, an n-hexyl group, a 2-ethylhexyl group, an n-octyl group, an n-decyl group, etc., and an alkyl group having 1 to 10 carbon atoms is preferred. The alkyl group may be linear or branched.

Examples of aryl groups that can substitute for hydrogen atoms in Ar ¹ , Ar ² or Ar ³ include phenyl, o-tolyl, m-tolyl, p-tolyl, 1-naphthyl and 2-naphthyl groups, and are preferably aryl groups having 6 to 20 carbon atoms. The aryl group may be a single ring or a condensed ring. The aryl group may also be a group in which a hydrogen atom in an aromatic ring is substituted with an alkyl group, such as a tolyl group.

When a hydrogen atom in Ar ¹ , Ar ² , or Ar ³ is substituted with the above-mentioned group, the number of substitutions is preferably 1 or 2, and more preferably 1. A hydrogen atom in Ar ¹ , Ar ² , or Ar ³ may not be substituted with the above-mentioned group.

In this embodiment, as an example, it is preferable that Ar ¹ is a 2,6-naphthylene group, Ar ² is a 1,4-phenylene group, a 1,3-phenylene group, or a 2,6-naphthylene group, and Ar ³ is a 1,4-phenylene group or a 1,3-phenylene group.

In this embodiment, it is particularly preferable that Ar ² is a 1,3-phenylene group. When Ar ² is a 1,3-phenylene group, the solubility in a solvent described below is further improved. This is believed to be because when Ar ² is a 1,3-phenylene group, a bent structure is introduced into the polymer.

In the present embodiment, from the viewpoints of favorable solubility in a solvent described below and of easily exhibiting adhesive strength and dielectric properties with a metal layer when laminated with a metal layer as a film, it is preferable that Ar ¹ is a 2,6-naphthylene group, Ar ² is a 1,3-phenylene group, Ar ³ is a 1,4-phenylene group, and Y is -O-.

The number of repeating units represented by the above formula (A1) is preferably 30% or more and 80% or less, more preferably 40% or more and 70% or less, and even more preferably 45% or more and 65% or less, relative to the total number (100%) of all repeating units constituting the liquid crystal polyester (A).
When the content of the repeating unit (A1) is equal to or less than the above upper limit, the solubility in a solvent is good, and when it is equal to or more than the above lower limit, the liquid crystallinity is good.

The number of repeating units represented by the above formula (A2) is preferably 10% or more and 35% or less, more preferably 15% or more and 30% or less, and even more preferably 17.5% or more and 27.5% or less, relative to the total number (100%) of all repeating units constituting the liquid crystal polyester (A).
When the content of the repeating unit (A2) is equal to or less than the above upper limit, the liquid crystallinity is good, and when it is equal to or more than the above lower limit, the solubility in a solvent is good.

The number of repeating units represented by the above formula (A3) is preferably 10% or more and 35% or less, more preferably 15% or more and 30% or less, and even more preferably 17.5% or more and 27.5% or less, relative to the total number (100%) of all repeating units constituting the liquid crystal polyester (A).
When the content of the repeating unit (A3) is equal to or less than the above upper limit, the liquid crystallinity is good, and when it is equal to or more than the above lower limit, the solubility in a solvent is good.

In addition, it is preferable that the number of repeating units (A2) and the number of repeating units (A3) in the liquid crystal polyester (A) are equal, but if the numbers are different, the difference between the numbers of repeating units (A2) and (A3) is preferably 10% or less.

The preferred proportion of each repeating unit in the liquid crystal polyester (A) is that the repeating unit represented by the above formula (A1) is preferably 30% or more and 80% or less, the repeating unit represented by the above formula (A2) is preferably 10% or more and 35% or less, and the repeating unit represented by the above formula (A3) is preferably 10% or more and 35% or less, relative to the total content of all repeating units constituting the liquid crystal polyester (A).

The preferred proportion of each repeating unit in the liquid crystal polyester (A) is that the repeating unit represented by the above formula (A1) is more preferably 40% or more and 70% or less, the repeating unit represented by the above formula (A2) is more preferably 15% or more and 30% or less, and the repeating unit represented by the above formula (A3) is more preferably 15% or more and 30% or less, relative to the total content of all repeating units constituting the liquid crystal polyester (A).

The preferred proportion of each repeating unit in the liquid crystal polyester (A) is that the repeating unit represented by the above formula (A1) is more preferably 45% or more and 65% or less, the repeating unit represented by the above formula (A2) is more preferably 17.5% or more and 27.5% or less, and the repeating unit represented by the above formula (A3) is more preferably 17.5% or more and 27.5% or less, relative to the total content of all repeating units constituting the liquid crystal polyester (A).

The liquid crystal polyester (A) may have two or more kinds of each of the repeating units (A1) to (A3). The liquid crystal polyester (A) may have repeating units other than the repeating units (A1) to (A3), but the number of such units is preferably 10% or less, more preferably 5% or less, and may be 0% based on the total number of all repeating units.

In this specification, the number of each repeating unit is determined by the analytical method described in JP-A-2000-19168.
Specifically, the liquid crystal polyester is depolymerized by reacting it with a lower alcohol in a supercritical state, and the depolymerization product (monomer from which each repeating unit is derived) is quantified by liquid chromatography, whereby the number of each repeating unit relative to the total number of repeating units can be calculated.

The repeating unit (A1) may be a repeating unit derived from an aromatic hydroxycarboxylic acid. The repeating unit (A2) may be a repeating unit derived from an aromatic dicarboxylic acid. The repeating unit (A3) may be a repeating unit derived from an aromatic hydroxylamine or a repeating unit derived from an aromatic diamine. The repeating units may be derived from ester or amide forming derivatives of the repeating units described above instead of the repeating units described above.

The method for producing the liquid crystal polyester (A) contained in this embodiment is not particularly limited, but examples include a method in which an aromatic hydroxy acid corresponding to the repeating unit (A1), an aromatic amine having a phenolic hydroxyl group corresponding to the repeating unit (A3), or a phenolic hydroxyl group or amino group of an aromatic diamine is acylated with an excess amount of a fatty acid anhydride to obtain an acylated product, and the obtained acylated product is melt-polymerized by ester-amide exchange (polycondensation) with an aromatic dicarboxylic acid corresponding to the repeating unit (A2) (see JP-A-2002-220444 and JP-A-2002-146003).

Polycondensation by ester exchange or amide exchange is usually carried out by melt polymerization. The polycondensation may be carried out by a combination of melt polymerization and solid-state polymerization.

The content of the liquid crystal polyester (A) may be 10% by mass or more and 90% by mass or less, 15% by mass or more and 50% by mass or less, or 25% by mass or more and 40% by mass or less, relative to the total solid content of the liquid crystal polyester composition of the embodiment.
The liquid crystal polyester composition containing the liquid crystal polyester (A) in the above numerical range can easily improve the adhesive strength to a metal layer and the dielectric properties of the produced film.

In this specification, the term "solid content" refers to components other than the solvent that may be contained in the liquid crystal polyester composition. Examples of the solvent include the aprotic solvents described below.

<Thermoplastic polyimide>
As an embodiment of the present invention, the thermoplastic resin may be a polyimide thermoplastic resin.
A liquid crystal polyester composition according to one embodiment of the present invention contains a liquid crystal polyester (A) and a thermoplastic polyimide, and the liquid crystal polyester (A) may have a repeating unit derived from an aromatic hydroxylamine or a repeating unit derived from an aromatic diamine.

The thermoplastic polyimide contained in the liquid crystal polyester composition of the embodiment exhibits the property of softening when heated (thermoplasticity). Hereinafter, the thermoplastic polyimide may be simply referred to as polyimide. The thermoplastic polyimide may be a crystalline polyimide.

The thermoplastic polyimide contained in the liquid crystal polyester composition of the embodiment may have a repeating unit represented by the following formula (I) and a repeating unit represented by the following formula (II).

(In the formula, R ₁ is a divalent group having 6 to 22 carbon atoms containing at least one alicyclic hydrocarbon structure. R ₂ is a divalent chain aliphatic group having 5 to 16 carbon atoms. X ₁ and X ₂ are each independently a tetravalent group having 6 to 22 carbon atoms containing at least one aromatic ring.)

The liquid crystal polyester composition of the embodiment contains a polyimide having the above-mentioned specific combination of different polyimide structural units, so that the effect of improving the adhesive strength with the metal layer is even more effectively exhibited.

The repeating unit of formula (I) is described in detail below.
_R1 is a divalent group containing at least one alicyclic hydrocarbon structure and having 6 to 22 carbon atoms. Here, the alicyclic hydrocarbon structure means a ring derived from an alicyclic hydrocarbon compound, and the alicyclic hydrocarbon compound may be saturated or unsaturated, and may be monocyclic or polycyclic.
Examples of the alicyclic hydrocarbon structure include, but are not limited to, a cycloalkane ring such as a cyclohexane ring, a cycloalkene ring such as a cyclohexene ring, a bicycloalkane ring such as a norbornane ring, and a bicycloalkene ring such as norbornene. Among these, a cycloalkane ring is preferred, a cycloalkane ring having 4 to 7 carbon atoms is more preferred, and a cyclohexane ring is even more preferred.

R ₁ is preferably a divalent group represented by the following formula (R1-1) or (R1-2).

( _m11 and _m12 each independently represent an integer of 0 to 2, preferably 0 or 1. _m13 to _m15 each independently represent an integer of 0 to 2, preferably 0 or 1.)

_R1 is particularly preferably a divalent group represented by the following formula (R1-3).

In the divalent group represented by the above formula (R1-3), the positional relationship of the two methylene groups to the cyclohexane ring may be either cis or trans, and the ratio of cis to trans may be any value.

_X1 is a tetravalent group having 6 to 22 carbon atoms and containing at least one aromatic ring. The aromatic ring may be a single ring or a condensed ring, and examples thereof include, but are not limited to, a benzene ring, a naphthalene ring, an anthracene ring, and a tetracene ring. Among these, a benzene ring and a naphthalene ring are preferred, and a benzene ring is more preferred.

_X1 is preferably a tetravalent group represented by any one of the following formulas (X-1) to (X-4).

(R ₁₁ to R ₁₈ are each independently an alkyl group having 1 to 4 carbon atoms. p ₁₁ to p ₁
p ₁₄ , p ₁₅ , p ₁₆ and p ₁₈ are each independently an integer of 0 to 3, preferably 0. p ₁₇ is an integer of 0 to 4, preferably 0. L ₁₁ to _{L 13 are} each independently a single bond, an ether group, a carbonyl group or an alkylene group having 1 to 4 carbon atoms.
Since _X1 is a tetravalent group containing at least one aromatic ring and having 6 to 22 carbon atoms, _R12 , _R13 , _p12 , and _p13 in formula (X-2) are selected so that the number of carbon atoms of the tetravalent group represented by formula (X-2) falls within the range of 6 to 22.
Similarly, L ₁₁ , R ₁₄ , R ₁₅ , p ₁₄ and p ₁₅ in formula (X-3) are selected so that the number of carbon atoms in the tetravalent group represented by formula (X-3) falls within the range of 6 to 22, and L ₁₂ , L ₁₃ , R ₁₆ , R ₁₇ , R ₁₈ , p ₁₆ , p _{17 and p 18 in} formula (X-4) are selected so that the number of carbon atoms in the tetravalent group represented by formula (X-4) falls within the range of 6 to 22.

_X1 is particularly preferably a tetravalent group represented by the following formula (X-5) or (X-6).

Next, the repeating unit of formula (II) will be described in detail below.
_R2 is a divalent chain aliphatic group having 5 to 16 carbon atoms, preferably 6 to 14 carbon atoms, more preferably 7 to 12 carbon atoms, and even more preferably 8 to 10 carbon atoms. Here, the chain aliphatic group means a group derived from a chain aliphatic compound, and the chain aliphatic compound may be saturated or unsaturated, may be linear or branched, and may contain a heteroatom such as an oxygen atom.
_R2 is preferably an alkylene group having 5 to 16 carbon atoms, more preferably an alkylene group having 6 to 14 carbon atoms, even more preferably an alkylene group having 7 to 12 carbon atoms, and particularly preferably an alkylene group having 8 to 10 carbon atoms. The alkylene group may be a linear alkylene group or a branched alkylene group, but is preferably a linear alkylene group.
_R2 is preferably at least one selected from an octamethylene group and a decamethylene group, and particularly preferably an octamethylene group.

Another preferred embodiment of _R2 is a divalent chain aliphatic group containing an ether group and having 5 to 16 carbon atoms. The number of carbon atoms is preferably 6 to 14, more preferably 7 to 12, and even more preferably 8 to 10. Among these, a divalent group represented by the following formula (R2-1) or (R2-2) is preferred.

( _m21 and _m22 each independently represent an integer from 1 to 15, preferably from 1 to 13,
More preferably, it is 1 to 11, and even more preferably, it is 1 to 9. _m23 to _m25 each independently represent an integer of 1 to 14, preferably 1 to 12, more preferably 1 to 10, and even more preferably 1 to 8.
Since R ₂ is a divalent chain aliphatic group having 5 to 16 carbon atoms (preferably 6 to 14 carbon atoms, more preferably 7 to 12 carbon atoms, and even more preferably 8 to 10 carbon atoms), m ₂₁ and m ₂₂ in formula (R2-1) are selected so that the number of carbon atoms in the divalent group represented by formula (R2-1) is in the range of 5 to 16 (preferably 6 to 14 carbon atoms, more preferably 7 to 12 carbon atoms, and even more preferably 8 to 10 carbon atoms). In other words, m ₂₁ +m ₂₂ is 5 to 16 (preferably 6 to 14, more preferably 7 to 12, and even more preferably 8 to 10).
Similarly, m ₂₃ to m ₂₅ in formula (R2-2) are selected so that the carbon number of the divalent group represented by formula (R2-2) is in the range of 5 to 16 (preferably 6 to 14 carbon atoms, more preferably 7 to 12 carbon atoms, and even more preferably 8 to 10 carbon atoms). In other words, m ₂₃ + m ₂₄ + m ₂₅ is 5 to 16 (preferably 6 to 14 carbon atoms, more preferably 7 to 12 carbon atoms, and even more preferably 8 to 10 carbon atoms).

_X2 is defined in the same manner as _X1 in formula (I), and preferred embodiments are also the same.

The content of the repeating unit of formula (I) relative to the total of the repeating units of formula (I) and formula (II) (100 mol %) may be 20 mol % or more and 70 mol % or less, or may be 20 mol % or more and less than 40 mol %.
The content ratio of the repeating unit of formula (I) to the total of the repeating unit of formula (I) and the repeating unit of formula (II) is preferably 25 mol % or more, more preferably 30 mol % or more, and even more preferably 32 mol % or more from the viewpoint of moldability, and is preferably 38 mol % or less, more preferably 36 mol % or less, and even more preferably 35 mol % or less from the viewpoint of improving heat resistance.

The total content of the repeating units of formula (I) and the repeating units of formula (II) relative to 100 mol% of all repeating units constituting the polyimide is preferably 50 to 100 mol%, more preferably 75 to 100 mol%, even more preferably 80 to 100 mol%, and even more preferably 85 to 100 mol%.

In the liquid crystal polyester composition, the content of the thermoplastic polyimide relative to 100 parts by mass of the liquid crystal polyester (A) may be 1 part by mass or more and 80 parts by mass or less, 3 parts by mass or more and 70 parts by mass or less, 5 parts by mass or more and 65 parts by mass or less, or 5 parts by mass or more and 15 parts by mass or less.

(Method for producing thermoplastic polyimide)
The thermoplastic polyimide can be produced by reacting a tetracarboxylic acid component with a diamine component, the tetracarboxylic acid component containing at least one aromatic ring and/or a derivative thereof, and the diamine component containing at least one alicyclic hydrocarbon structure and a chain aliphatic diamine.

As a polymerization method for producing thermoplastic polyimide, a known polymerization method capable of producing thermoplastic polyimide can be applied, such as solution polymerization, melt polymerization, solid-phase polymerization, suspension polymerization, etc.

<Aromatic polysulfone>
As one embodiment of the present invention, the thermoplastic resin may be an aromatic polysulfone.

The liquid crystal polyester composition of one embodiment of the present invention contains a liquid crystal polyester (A) and an aromatic polysulfone, and the liquid crystal polyester (A) may have a repeating unit derived from an aromatic hydroxylamine or a repeating unit derived from an aromatic diamine.

In this specification, aromatic polysulfone is a resin having a repeating unit containing a divalent aromatic group (a residue obtained by removing two hydrogen atoms bonded to an aromatic ring from an aromatic compound), an ether bond (-O-), and a sulfonyl group (-SO ₂ -).

The aromatic polysulfone may have at least one hydroxy group, amino group, or halogen atom at the end of the main chain, or may have at least one hydroxy group at the end of the main chain.
Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, with a chlorine atom being preferred.

From the viewpoint of excellent heat resistance and chemical resistance, it is preferable that the aromatic polysulfone has a repeating unit represented by the following formula (S1) (hereinafter, sometimes referred to as "repeating unit (S1)"). In addition to the repeating unit (S1), it may further have one or more other repeating units such as a repeating unit represented by the following formula (S2) (hereinafter, sometimes referred to as "repeating unit (S2)") or a repeating unit represented by the following formula (S3) (hereinafter, sometimes referred to as "repeating unit (S3)").

(S1) -Ph ¹ -SO ₂ -Ph ² -O-
In the formula, ^Ph1 and ^Ph2 each independently represent a phenylene group. A hydrogen atom in the phenylene group each independently represents an alkyl group, an aryl group, a halogen atom, a sulfo group, a nitro group, an amino group, , a carboxyl group, or a hydroxyl group.

(S2)-Ph ³ -R-Ph ⁴ -O-
In the formula, ^Ph3 and ^Ph4 each independently represent a phenylene group. A hydrogen atom in the phenylene group each independently represents an alkyl group, an aryl group, a halogen atom, a sulfo group, a nitro group, an amino group, , a carboxyl group, or a hydroxyl group; R represents an alkylidene group, an oxygen atom, or a sulfur atom.

(S3)-(Ph ⁵ ) _n -O-
In the formula, ^Ph5 represents a phenylene group. Each hydrogen atom in the phenylene group is independently an alkyl group, an aryl group, a halogen atom, a sulfo group, a nitro group, an amino group, a carboxyl group, or a hydroxyl group. n represents an integer of 1 to 3. When n is 2 or more, a plurality of Ph ⁵ 's may be the same or different.

The phenylene group represented by any one of Ph ¹ to Ph ⁵ may be a p-phenylene group, an m-phenylene group, or an o-phenylene group, but is preferably a p-phenylene group.

The alkyl group that may replace the hydrogen atom in the phenylene group preferably has 1 to 10 carbon atoms. Specific examples include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, s-butyl, t-butyl, n-hexyl, 2-ethylhexyl, n-octyl, and n-decyl groups.

In the aryl group that may replace the hydrogen atom in the phenylene group, the carbon number is preferably 6 to 20. Specific examples include a phenyl group, an o-tolyl group, an m-tolyl group, a p-tolyl group, a 1-naphthyl group, and a 2-naphthyl group.

Examples of halogen atoms that may replace hydrogen atoms in the phenylene group include fluorine atoms, chlorine atoms, bromine atoms, and iodine atoms.

When hydrogen atoms in the phenylene groups are substituted with these groups, the number of such groups is preferably 2 or less, more preferably 1, independently for each phenylene group.
Among the above, it is preferred that the hydrogen atoms in the phenylene group are not substituted.

In the alkylidene group represented by R, the carbon number is preferably 1 to 5. Specific examples include a methylene group, an ethylidene group, an isopropylidene group, and a 1-butylidene group.

The aromatic polysulfone preferably has 50% or more of the repeating unit (S1) relative to the total of all repeating units (100%), more preferably 80% or more, and even more preferably has substantially only the repeating unit (S1) as the repeating unit. The aromatic polysulfone may have two or more types of repeating units (S1) to (S3) independently.

The viscosity of the following measurement solution containing aromatic polysulfone, measured using a B-type viscometer (e.g., TV-22, manufactured by Toki Sangyo Co., Ltd.) under conditions of a sample temperature of 23°C and a rotor rotation speed of 20 rpm, is preferably 100 mPa·s or more and 5000 mPa·s or less, more preferably 300 mPa·s or more and 4000 mPa·s or less, and even more preferably 2500 mPa·s or more and 3500 mPa·s or less.
Measurement solution: A solution obtained by adding 25 parts by mass of the aromatic polysulfone powder to be measured to 75 parts by mass of N-methylpyrrolidone and stirring the mixture at 100° C. for 4 hours in a nitrogen atmosphere.

When the viscosity of the measurement solution is within the above-mentioned preferred range, the liquid crystal polyester composition containing aromatic polysulfone has an even more excellent effect of improving the adhesive strength with the metal layer.

In this embodiment, the aromatic polysulfone may be used alone or in combination of two or more types.

In the liquid crystal polyester composition, the content of aromatic polysulfone relative to 100 parts by mass of the liquid crystal polyester (A) may be, for example, 1 part by mass or more and 80 parts by mass or less, 3 parts by mass or more and 70 parts by mass or less, 5 parts by mass or more and 65 parts by mass or less, or 5 parts by mass or more and 60 parts by mass or less.

[Method of producing aromatic polysulfone]
The aromatic polysulfone can be produced by polycondensing a dihalogenosulfone compound and a dihydroxy compound corresponding to the repeating unit constituting the aromatic polysulfone.

For example, a resin having repeating unit (S1) can be produced by using a compound represented by the following formula (S4) (hereinafter also referred to as "compound (S4)") as the dihalogenosulfone compound and a compound represented by the following formula (S5) as the dihydroxy compound.

For example, a resin having repeating units (S1) and (S2) can be produced by using compound (S4) as the dihalogenosulfone compound and a compound represented by the following formula (S6) as the dihydroxy compound.

For example, a resin having repeating units (S1) and (S3) can be produced by using compound (S4) as the dihalogenosulfone compound and a compound represented by the following formula (S7) as the dihydroxy compound.

(S4)X ¹ -Ph ¹ -SO ₂ -Ph ² -X ²
[In the formula, ^X1 and ^X2 each independently represent a halogen atom. ^Ph1 and ^Ph2 are as defined above.]

(S5) HO-Ph ¹ -SO ₂ -Ph ² -OH
[In the formula, Ph ¹ and Ph ² are as defined above.]

(S6) HO-Ph ³ -R-Ph ⁴ -OH
[In the formula, Ph ³ , Ph ⁴ and R are as defined above.]

(S7) HO-(Ph ⁵ ) _n -OH
[In the formula, ^Ph5 and n are as defined above.]

The polycondensation of aromatic polysulfone is preferably carried out in a solvent using an alkali metal salt of carbonate. The alkali metal salt of carbonate may be a carbonate, which is a normal salt, a bicarbonate (hydrogen carbonate), which is an acidic salt, or a mixture of the two. As the carbonate, sodium carbonate or potassium carbonate is preferably used, and as the hydrogen carbonate, sodium bicarbonate or potassium bicarbonate is preferably used.

As the solvent for polycondensation, an organic polar solvent is preferably used. Specific examples include dimethyl sulfoxide, 1-methyl-2-pyrrolidone, sulfolane (1,1-dioxothiane), 1,3-dimethyl-2-imidazolidinone, 1,3-diethyl-2-imidazolidinone, dimethyl sulfone, diethyl sulfone, diisopropyl sulfone, diphenyl sulfone, etc.

<Optional ingredients>
Examples of optional components that the liquid crystal polyester composition of the embodiment may further contain as necessary include liquid crystal polyesters other than the liquid crystal polyester (A), particles such as fillers, solvents that dissolve the liquid crystal polyester (A), additives, etc.

Additives include antioxidants, heat stabilizers, UV absorbers, antistatic agents, surfactants, flame retardants, colorants, etc.

An example of a liquid crystal polyester that does not fall under liquid crystal polyester (A) is liquid crystal polyester (B) described below. The particles may be liquid crystal polyester particles that contain liquid crystal polyester (B).

The liquid crystal polyester (B) may be insoluble in the solvent described below, and may be present as particles in the liquid crystal polyester composition even if the composition contains a solvent.

(Liquid Crystal Polyester (B))
The liquid crystal polyester composition may further contain a liquid crystal polyester (B).

The liquid crystal polyester (B) is a liquid crystal polyester that does not fall under the category of the liquid crystal polyester (A). The liquid crystal polyester (B) may be a liquid crystal polyester that does not have a repeating unit derived from an aromatic hydroxylamine and a repeating unit derived from an aromatic diamine.
The liquid crystal polyester (B) may be a liquid crystal polyester having a repeating unit represented by the following formula (B1) and having no repeating unit derived from an aromatic hydroxylamine or no repeating unit derived from an aromatic diamine.

The liquid crystal polyester (B) is
It is preferable that the liquid crystal polyester has a repeating unit represented by the following formula (B1).
(B1) -O-Ar ^b1 -CO-
(Ar ^b1 represents a phenylene group, a naphthylene group or a biphenylylene group.
Each hydrogen atom in the group represented by Ar ^b1 may be independently substituted with a halogen atom, an alkyl group, or an aryl group.

Examples of the phenylene group, naphthylene group, and biphenylylene group in Ar ^b1 include those exemplified in the liquid crystal polyester (A).

Examples of the halogen atom, alkyl group or aryl group in Ar ^b1 include those exemplified in the liquid crystal polyester (A) above.

In the liquid crystal polyester (B), the higher the content of the repeating unit represented by the formula (B1) in the liquid crystal polyester composition, the better the effect of suppressing the increase in viscosity due to a temperature drop, and the better the processing characteristics.
From this viewpoint, the number of repeating units represented by the formula (B1) relative to the total number (100%) of all repeating units constituting the liquid crystal polyester (B) is preferably more than 80%, more preferably 85% or more and 100% or less, more preferably 90% or more and 100% or less, more preferably 95% or more and 100% or less, and even more preferably 98% or more and 100% or less. It is particularly preferable that the liquid crystal polyester (B) is substantially composed only of repeating units represented by the formula (B1), i.e., the number of repeating units represented by the formula (B1) is 100%.

From the viewpoint of being contained in the liquid crystal polyester composition and being more excellent in the effect of suppressing the increase in viscosity due to a temperature drop, the liquid crystal polyester (B) listed above is preferably:
The repeating unit represented by the formula (B1) is
It is preferable that the polymer contains a repeating unit represented by the following formula (B1-1).
(B1-1)-O-Ar ^b1-1 -CO-
(Ar ^b1-1 represents a naphthylene group.
Each hydrogen atom in the group represented by Ar ^b1-1 may be independently substituted with a halogen atom, an alkyl group, or an aryl group.

The number of repeating units represented by formula (B1-1) is preferably more than 50% and not more than 90%, and more preferably 65 to 80%, relative to the total number (100%) of repeating units corresponding to formula (B1).
When the content ratio of the repeating unit represented by the formula (B1-1) in the liquid crystal polyester (B) is within the above numerical range, the liquid crystal polyester composition is contained therein, and thus the effect of suppressing the increase in viscosity due to a temperature drop is further improved, and an excellent dielectric tangent can be exhibited.

More specifically, in the liquid crystal polyester (B) described above, the repeating unit represented by the formula (B1) preferably contains a repeating unit represented by the following formula (B1-1) and a repeating unit represented by the following formula (B1-2), and more preferably consists of only a repeating unit represented by the following formula (B1-1) and a repeating unit represented by the following formula (B1-2).
(B1-1)-O-Ar ^b1-1 -CO-
(B1-2)-O-Ar ^b1-2 -CO-
(Ar ^b1-1 represents a naphthylene group.
Ar ^b1-2 represents a phenylene group.
The hydrogen atoms in the groups represented by Ar ^b1-1 and Ar ^b1-2 may each independently be substituted with a halogen atom, an alkyl group, or an aryl group.

Examples of the naphthylene group in Ar ^b1-1 include those exemplified in the liquid crystal polyester (A) above.
Examples of the phenylene group in Ar ^b1-2 include those exemplified in the liquid crystal polyester (A) above.

As the halogen atom, alkyl group or aryl group in Ar ^b1-1 and Ar ^b1-2 , those exemplified in the liquid crystal polyester (A) above can be mentioned.

More specifically, the liquid crystal polyester (B) described above is composed only of a repeating unit represented by the formula (B1), and the repeating unit represented by the formula (B1) preferably contains a repeating unit represented by the following formula (B1-1) and a repeating unit represented by the following formula (B1-2), and more preferably consists only of a repeating unit represented by the following formula (B1-1) and a repeating unit represented by the following formula (B1-2).
(B1-1)-O-Ar ^b1-1 -CO-
(B1-2)-O-Ar ^b1-2 -CO-
(Ar ^b1-1 represents a 2,6-naphthylene group.
Ar ^b1-2 represents a 1,4-phenylene group.
The hydrogen atoms in the groups represented by Ar ^b1-1 and Ar ^b1-2 may each independently be substituted with a halogen atom, an alkyl group having 1 to 10 carbon atoms, or an aryl group having 6 to 20 carbon atoms.

The repeating unit represented by the above formula (B1) is a repeating unit derived from an aromatic hydroxycarboxylic acid. Examples of the repeating unit derived from an aromatic hydroxycarboxylic acid include those exemplified as the repeating unit represented by the above formula (A1).

When the repeating unit represented by formula (B1) contains a repeating unit represented by formula (B1-1) below and a repeating unit represented by formula (B1-2) below, for example, the repeating unit represented by formula (B1-2) is represented by the following formula (B1-3) based on the total number (100%) of all repeating units constituting the liquid crystal polyester (B):
The number of repeating units represented by the formula (B1-1) is more than 50% and 90% or less,
The number of repeating units represented by formula (B1-2) may be 10% or more and less than 50%.
The number of repeating units represented by the formula (B1-1) is 65% or more and 80% or less,
The number of repeating units represented by the formula (B1-2) may be 20% or more and 35% or less.

The liquid crystal polyester (B) may have two or more repeating units represented by the formula (B1), each of which is independent of the other repeating units. The liquid crystal polyester may have repeating units other than the repeating units represented by the formula (B1), but the content of such repeating units is preferably 10% or less, more preferably 5% or less, and may even be 0%, relative to the total number (100%) of all repeating units constituting the liquid crystal polyester (B).

When the liquid crystal polyester composition contains the liquid crystal polyester (A) and the liquid crystal polyester (B), the content ratio of the liquid crystal polyester (A) to the liquid crystal polyester (B) in the liquid crystal polyester composition is preferably liquid crystal polyester (A)/liquid crystal polyester (B)=80/20 to 10/90, more preferably 70/30 to 20/80, and even more preferably 50/50 to 30/70, in terms of a good balance between the dielectric properties and the above-mentioned adhesion strength.

The ratio of the total content rate of liquid crystal polyester (A) and liquid crystal polyester (B) to the total mass (100 mass%) of the liquid crystal polyester contained in the liquid crystal polyester composition of the embodiment may be 50 mass% or more, 80 mass% or more, or 100 mass%.

When the liquid crystal polyester composition contains the liquid crystal polyester (A) and the liquid crystal polyester (B), the content of the thermoplastic resin in the liquid crystal polyester composition relative to a total of 100 parts by mass of the liquid crystal polyester (A) and the liquid crystal polyester (B) is preferably 0.5 parts by mass or more, more preferably 1 part by mass or more, and even more preferably 2 parts by mass or more.
A liquid crystal polyester composition containing a thermoplastic resin in an amount not less than the above lower limit is more excellent in the effect of improving the adhesive strength with a metal layer.

In the liquid crystal polyester composition, the content of the thermoplastic resin relative to 100 parts by mass in total of the liquid crystal polyester (A) and the liquid crystal polyester (B) is preferably 50 parts by mass or less, more preferably 30 parts by mass or less, and even more preferably 25 parts by mass or less.
A liquid crystal polyester composition containing a thermoplastic resin at or below the above upper limit has even more excellent dielectric properties.

In the liquid crystal polyester composition, the content of the thermoplastic resin relative to a total of 100 parts by mass of the liquid crystal polyester (A) and the liquid crystal polyester (B) may be, for example, in the range of values from 0.5 parts by mass to 50 parts by mass, from 1 part by mass to 30 parts by mass, or from 2 parts by mass to 25 parts by mass.

As an example of the liquid crystal polyester composition of one embodiment of the present invention, there is exemplified the liquid crystal polyester composition according to any one of <1> to <11>, which further contains a liquid crystal polyester (B), in which the content ratio of the liquid crystal polyester (A) to the liquid crystal polyester (B) in the liquid crystal polyester composition is liquid crystal polyester (A)/liquid crystal polyester (B) = 80/20 to 10/90 in mass ratio, and the content of the thermoplastic resin is 0.5 parts by mass or more and 50 parts by mass or less with respect to 100 parts by mass of the total of the liquid crystal polyester (A) and the liquid crystal polyester (B).

Here, the total of liquid crystal polyester (A) and liquid crystal polyester (B) is preferably the total of liquid crystal polyester particles containing liquid crystal polyester (A) and liquid crystal polyester (B), which will be described later, and the content value can be the same as the value exemplified above.

The flow initiation temperature of the liquid crystal polyester composition of the embodiment containing the liquid crystal polyester (A) and the liquid crystal polyester (B) is preferably 260°C or higher, more preferably 260°C or higher and 400°C or lower, and even more preferably 260°C or higher and 380°C or lower.
The higher the flow initiation temperature of the liquid crystal polyester composition, the more the heat resistance and strength of the liquid crystal polyester composition tend to improve. On the other hand, when the flow initiation temperature of the liquid crystal polyester composition exceeds 400° C., the melting temperature and melt viscosity of the liquid crystal polyester composition tend to increase. Therefore, the temperature required for molding the liquid crystal polyester composition tends to increase.

The flow initiation temperature of the liquid crystal polyester (A) may be the same as the values exemplified as the flow initiation temperatures of the liquid crystal polyester compositions of the embodiments.

The flow initiation temperature of the liquid crystal polyester (B) may be the same as the values exemplified as the flow initiation temperatures of the liquid crystal polyester compositions of the embodiments.

In this specification, the flow initiation temperature of the liquid crystal polyester composition is also called the flow temperature or flow temperature, and is a temperature that is an indicator of the molecular weight of the liquid crystal polyester (see Naoyuki Koide, ed., Liquid Crystal Polymer - Synthesis, Forming, and Application -, CMC Co., Ltd., June 5, 1987, p. 95).
The flow initiation temperature is the temperature at which the liquid crystal polyester composition exhibits a viscosity of 4,800 Pa·s ( ^48,000 poise) when the liquid crystal polyester composition is melted using a flow tester while being heated at a rate of 4°C/min under a load of 9.8 MPa (100 kg/cm 2 ) and extruded from a nozzle having an inner diameter of 1 mm and a length of 10 mm.

(particle)
The liquid crystal polyester composition of the embodiment may contain particles. Examples of the particles include liquid crystal polyester particles as well as fillers.

When the liquid crystal polyester composition contains particles, the adhesive strength with the metal layer may decrease when the liquid crystal polyester composition is laminated to the metal layer as a film. However, the liquid crystal polyester composition of one embodiment of the present invention contains at least one thermoplastic resin selected from the group consisting of thermoplastic polyimide and aromatic polysulfone, and therefore has excellent adhesive strength with the metal layer.

Liquid Crystal Polyester Particles The liquid crystal polyester particles are preferably liquid crystal polyester particles containing the liquid crystal polyester (B).

The _D50 of the liquid crystal polyester particles is preferably 30 μm or less, more preferably 20 μm or less, more preferably 18 μm or less, even more preferably 15 μm or less, and particularly preferably 12 μm or less. When the _D50 of the liquid crystal polyester is 20 μm or less, a film having a thickness suitable for use as a film for electronic components (for example, 50 μm or less) and excellent surface smoothness can be easily produced.
From the viewpoint of ease of handling of the particles, the lower limit of _D50 of the liquid crystal polyester particles is preferably 0.1 μm or more, more preferably 0.5 μm or more, further preferably 3 μm or more, and particularly preferably 5 μm or more.
The upper limit and the lower limit of the _D50 value of the liquid crystal polyester particles can be freely combined. The numerical range of the _D50 value of the liquid crystal polyester particles may be 0.1 to 30 μm, 0.5 to 30 μm, 0.5 to 20 μm, 3 to 18 μm, 5 to 15 μm, or 5 to 12 μm.

The particle diameter _D50 of the liquid crystal polyester particles is a value determined by the following measurement method.

[Measurement of particle diameter _D50 of liquid crystal polyester particles]
The particle diameter _D50 of the liquid crystal polyester particles is measured using a scattering type particle diameter distribution measuring device (for example, LA-950V2 manufactured by Horiba, Ltd.) The refractive index of pure water is set to 1.333, and the volume-based cumulative particle size distribution of the liquid crystal polyester particles is measured, and the particle diameter (μm) at which the cumulative volume ratio is 50% is calculated as the particle diameter _D50 .

As an example of a liquid crystal polyester composition according to one embodiment of the present invention, there is provided a liquid crystal polyester composition according to any one of <1> to <11>, which contains liquid crystal polyester (A), a thermoplastic polyimide, and liquid crystal polyester particles containing liquid crystal polyester (B), in which the liquid crystal polyester (A) has a repeating unit derived from an aromatic hydroxylamine or a repeating unit derived from an aromatic diamine, and the liquid crystal polyester (B) does not have a repeating unit derived from an aromatic hydroxylamine or a repeating unit derived from an aromatic diamine.

As an example of a liquid crystal polyester composition according to one embodiment of the present invention, there is provided a liquid crystal polyester composition according to any one of <1> to <11>, which contains liquid crystal polyester (A), aromatic polysulfone, and liquid crystal polyester particles containing liquid crystal polyester (B), in which the liquid crystal polyester (A) has a repeating unit derived from an aromatic hydroxylamine or a repeating unit derived from an aromatic diamine, and the liquid crystal polyester (B) does not have a repeating unit derived from an aromatic hydroxylamine or a repeating unit derived from an aromatic diamine.

Filler The filler may be a fibrous filler, a plate-like filler, or a granular filler.
Examples of the filler include inorganic fillers such as silica, alumina, titanium oxide, barium titanate, strontium titanate, aluminum hydroxide, calcium carbonate, etc.; and organic fillers such as cured epoxy resins, crosslinked benzoguanamine resins, crosslinked acrylic resins, etc.

When the liquid crystal polyester composition of the embodiment contains particles, the content of the particles (preferably liquid crystal polyester particles) is preferably 5% by mass or more, more preferably 20% by mass or more, even more preferably 30% by mass or more, and particularly preferably 50% by mass or more, relative to 100% by mass of the total solid content of the liquid crystal polyester composition.
The content of the particles (preferably liquid crystal polyester particles) in the liquid crystal polyester composition of the embodiment is preferably 80 mass% or less, more preferably 70 mass% or less, and even more preferably 60 mass% or less, relative to 100 mass% of the total solid content of the liquid crystal polyester composition.
An example of the numerical range of the content of the particles (preferably liquid crystal polyester particles) in the liquid crystal polyester composition of the embodiment may be 5% by mass or more and 80% by mass or less, 20% by mass or more and 70% by mass or less, 30% by mass or more and 60% by mass or less, or 50% by mass or more and 60% by mass or less.

By containing, for example, liquid crystal polyester particles at or above the lower limit, the particle characteristics are well exhibited. For example, the dielectric characteristics of the film produced can be further improved. In addition, by using a liquid crystal polyester composition containing liquid crystal polyester particles at or below the upper limit, the adhesive strength of the film produced with the metal layer can be further improved.

(solvent)
The liquid crystal polyester composition of the embodiment may further contain a solvent capable of dissolving the liquid crystal polyester (A).

As one embodiment of the present invention, a liquid crystal polyester composition can be provided, which contains a liquid crystal polyester (A), at least one thermoplastic resin selected from the group consisting of a thermoplastic polyimide and an aromatic polysulfone, and a solvent capable of dissolving the liquid crystal polyester (A).
The liquid crystal polyester composition of <11> may be substituted for the liquid crystal polyester composition of <1> by the liquid crystal polyester compositions of <2> to <10>.

The solvent may be an aprotic solvent, which has the advantage of being less corrosive and easier to handle.
In this embodiment, the aprotic solvent is a solvent containing an aprotic compound.
In the present embodiment, examples of the aprotic solvent include halogen-based solvents such as 1-chlorobutane, chlorobenzene, 1,1-dichloroethane, 1,2-dichloroethane, chloroform, and 1,1,2,2-tetrachloroethane; ether-based solvents such as diethyl ether, tetrahydrofuran, and 1,4-dioxane; ketone-based solvents such as acetone and cyclohexanone; ester-based solvents such as ethyl acetate; lactone-based solvents such as γ-butyrolactone; carbonate-based solvents such as ethylene carbonate and propylene carbonate; amine-based solvents such as triethylamine and pyridine; nitrile-based solvents such as acetonitrile and succinonitrile; amide-based solvents such as N,N'-dimethylformamide, N,N'-dimethylacetamide, tetramethylurea, and N-methylpyrrolidone; nitro-based solvents such as nitromethane and nitrobenzene; sulfide-based solvents such as dimethyl sulfoxide and sulfolane; and phosphoric acid-based solvents such as hexamethylphosphoric acid amide and tri-n-butyl phosphoric acid. A mixture of two or more of these may be used.

Among these, aprotic compounds that do not have halogen atoms are preferably used in terms of their impact on the environment, and solvents with a dipole moment of 3 to 5 are preferably used in terms of solubility. Specifically, amide solvents such as N,N'-dimethylformamide, N,N'-dimethylacetamide, tetramethylurea, and N-methylpyrrolidone, or lactone solvents such as γ-butyrolactone are more preferably used, and N,N'-dimethylformamide, N,N'-dimethylacetamide, or N-methylpyrrolidone are even more preferably used.

In the liquid crystal polyester composition of the embodiment, the ratio of the solvent content to the total mass of the liquid crystal polyester composition may be 20% by mass or more, may be 20% by mass or more and 99% by mass or less, or may be 50% by mass or more and 95% by mass or less, from the viewpoint of reducing the viscosity of the liquid crystal polyester composition and facilitating application to a support.

When the liquid crystal polyester composition of the embodiment further contains the solvent, the liquid crystal polyester composition may be a liquid composition.

In this specification, the term "liquid composition" refers to a solution or dispersion that is liquid at room temperature and pressure (25°C, 1 atm). A dispersion refers to a solution in which solids that are not dissolved are dispersed. Examples of the solids to be dispersed include the above-mentioned liquid crystal polyester particles, thermoplastic polyimide, and fillers.

As an example of a liquid crystal polyester composition according to one embodiment of the present invention, there is provided a liquid crystal polyester composition according to any one of <1> to <11>, which contains liquid crystal polyester (A), a thermoplastic polyimide, liquid crystal polyester particles containing liquid crystal polyester (B), and a solvent capable of dissolving the liquid crystal polyester (A), in which the liquid crystal polyester (A) has a repeating unit derived from an aromatic hydroxylamine or a repeating unit derived from an aromatic diamine, and the liquid crystal polyester (B) does not have a repeating unit derived from an aromatic hydroxylamine or a repeating unit derived from an aromatic diamine.

As an example of a liquid crystal polyester composition according to one embodiment of the present invention, there is provided a liquid crystal polyester composition according to any one of <1> to <11>, which contains liquid crystal polyester (A), aromatic polysulfone, liquid crystal polyester particles containing liquid crystal polyester (B), and a solvent capable of dissolving the liquid crystal polyester (A), in which the liquid crystal polyester (A) has a repeating unit derived from an aromatic hydroxylamine or a repeating unit derived from an aromatic diamine, and the liquid crystal polyester (B) does not have a repeating unit derived from an aromatic hydroxylamine or a repeating unit derived from an aromatic diamine.

The liquid crystal polyester composition of the embodiment contains a liquid crystal polyester and at least one thermoplastic resin selected from the group consisting of thermoplastic polyimide and aromatic polysulfone, and when laminated with a metal layer as a film, the adhesive strength with the metal layer is improved compared to a case where the thermoplastic resin is not contained.

The liquid crystal polyester composition of the embodiment further contains liquid crystal polyester (B), so that the liquid crystal polyester composition can be endowed with the properties of liquid crystal polyester (B). The properties may vary depending on the composition of liquid crystal polyester (B), but may include, for example, excellent dielectric properties and good processing properties.

In addition, by including liquid crystal polyester (B) in the form of liquid crystal polyester particles, the dispersibility of liquid crystal polyester (B) in the composition is improved, even when a solvent that does not dissolve liquid crystal polyester (B) is included, and a high-quality film can be obtained.

<Film>
The film of the embodiment contains a liquid crystal polyester (A) and at least one thermoplastic resin selected from the group consisting of a thermoplastic polyimide and an aromatic polysulfone, and the liquid crystal polyester (A) has a repeating unit derived from an aromatic hydroxylamine or a repeating unit derived from an aromatic diamine.

Figure 1 is a cross-sectional view showing the configuration of the film 10 of the embodiment.

Examples of the liquid crystal polyester (A) include those described in the above section "Liquid crystal polyester composition," and detailed description here will be omitted. Note that the liquid crystal polyester (A) in the state formed into a film may not be soluble in a solvent (e.g., an aprotic solvent) due to changes in physical properties that occur during the film formation process. The above-mentioned changes in physical properties are, for example, an increase in the degree of polymerization.

The at least one thermoplastic resin selected from the group consisting of thermoplastic polyimide and aromatic polysulfone can be one described above in the section on liquid crystal polyester composition, and a detailed description thereof will be omitted here.

The film described in <12> above may have the following aspects:

<15> As an embodiment of the film, the liquid crystalline polyester (A) has a repeating unit derived from an aromatic hydroxylamine or a repeating unit derived from an aromatic diamine, and the liquid crystalline polyester (A) has a repeating unit represented by the following formula (A1), a repeating unit represented by the following formula (A2), and a repeating unit represented by the following formula (A3).
(A1)-O-Ar ¹ -CO-
(A2) -CO-Ar ² -CO-
(A3)-X-Ar ³ -Y-
(Wherein,
Ar ¹ represents a 1,4-phenylene group, a 2,6-naphthylene group, or a 4,4'-biphenylene group; Ar ² represents a 1,4-phenylene group, a 1,3-phenylene group, or a 2,6-naphthylene group; Ar ³ represents a 1,4-phenylene group or a 1,3-phenylene group; X represents -NH-; and Y represents -O- or -NH-.
The hydrogen atoms in the groups represented by Ar ¹ , Ar ² and Ar ³ may each independently be substituted with a halogen atom, an alkyl group or an aryl group.

<16> Further, the liquid crystal polyester composition contains liquid crystal polyester particles including a liquid crystal polyester (B),
The film according to <12> or <15>, wherein the liquid crystal polyester (B) does not have a repeating unit derived from an aromatic hydroxylamine and a repeating unit derived from an aromatic diamine.

<17> The film according to <16>, wherein the content of the liquid crystal polyester particles is 5% by mass or more and 80% by mass or less with respect to 100% by mass of the total content of solids contained in the liquid crystal polyester composition.

<18> The film according to any one of <12> and <15> to <17>, wherein the content of the thermoplastic resin is 1 part by mass or more per 100 parts by mass of the liquid crystal polyester (A).

<19> The film according to any one of <12> and <15> to <18>, wherein the content of the liquid crystal polyester (A) is 10% by mass or more and 90% by mass or less, relative to 100% by mass of the total mass of the film.

<20> The film according to any one of <12> and <15> to <19>, wherein the thermoplastic resin is a thermoplastic polyimide.

<21> The film according to <20>, wherein the thermoplastic polyimide has a repeating unit represented by the formula (I) and a repeating unit represented by the following formula (II):

<22> The film according to <21>, wherein the content of the repeating unit of the formula (I) in the thermoplastic polyimide is 20 mol% or more and 70 mol% or less with respect to the total 100 mol% of the repeating unit of the formula (I) and the repeating unit of the formula (II).

The film of the embodiment may contain, as in the liquid crystal polyester composition of the above embodiment, liquid crystal polyester (A) and at least one thermoplastic resin selected from the group consisting of thermoplastic polyimide and aromatic polysulfone, as well as other optional components as necessary, and detailed description thereof will be omitted here.

The film of the embodiment preferably contains a liquid crystal polyester (A), at least one thermoplastic resin selected from the group consisting of thermoplastic polyimide and aromatic polysulfone, and particles.
In the film of the embodiment, the particles are preferably liquid crystal polyester particles. Note that the liquid crystal polyester particles in a state formed into a film do not need to have a particle shape that can be distinguished due to changes in physical properties during the film formation process.

The content of each component in the film of the embodiment can be the same as the content of each component as the solid content of the liquid crystal polyester composition of the embodiment exemplified above.

The thickness of the film in the embodiment is not particularly limited, but a suitable thickness for a film for electronic components is preferably 5 to 50 μm, more preferably 7 to 40 μm, even more preferably 10 to 33 μm, and particularly preferably 15 to 30 μm.

The method for producing the film of the embodiment is not particularly limited, and can be obtained, for example, by forming the liquid crystal polyester composition of the embodiment into a film. From the viewpoint of being able to produce a film having excellent isotropy, the film of the embodiment is preferably produced by the <<Film Production Method>> described below.

<Film manufacturing method>
The method for producing the film of the embodiment includes applying the liquid crystal polyester composition of the embodiment onto a support to obtain a film.

When the liquid crystal polyester composition contains a solvent, the method for producing a film of the embodiment may include applying the liquid crystal polyester composition of the embodiment onto a support and removing the solvent from the liquid crystal polyester composition to obtain a film.
The manufacturing method may be a solution casting method.

Examples of the liquid crystal polyester composition of the embodiment include those exemplified in the above "Liquid crystal polyester composition".

The method for producing the film may include the following steps.
A step of applying the liquid crystal polyester composition of the embodiment onto a support (application step).
A step of removing the solvent from the applied liquid crystal polyester composition (drying step).

The method for producing a film according to the embodiment may include a step of heat-treating the liquid crystal polyester composition or the precursor of the film from which the solvent has been removed (heat treatment step) after the coating step.

The method for producing a film of the embodiment may include applying the liquid crystal polyester composition of the embodiment onto a support, removing the solvent from the liquid crystal polyester composition, and heat treating the composition to obtain a film. The heat treatment can promote the polymerization reaction of the polymer in the liquid crystal polyester composition and can also promote the evaporation of the solvent.

The heat treatment can also serve as the drying step.
The method for producing the film of the embodiment may include applying the liquid crystal polyester composition of the embodiment onto a support, and heat treating the applied composition to obtain a film.

The film manufacturing method may further include a step of separating the support from the laminate (separation step). Note that the film can be suitably used as a film for electronic components even when it is formed as a laminate on the support, so the separation step is not an essential step in the film manufacturing process.

Below, an example of a method for producing a film of an embodiment when the liquid crystal polyester composition contains a solvent will be described with reference to the drawings.

3A to 3D are schematic diagrams showing an example of a process for producing the film of the embodiment.
First, the liquid crystal polyester composition 30 is applied onto the support 12 (FIG. 3A: application step).

Examples of the support 12 include a glass plate, a resin film, and a metal foil. Among them, the support 12 is preferably a resin film or a metal foil, and in particular, copper foil is preferred because it has excellent heat resistance, is easy to apply the liquid crystal polyester composition to, and is easy to remove from the film.
The thickness of the resin film is usually from 25 μm to 75 μm, and preferably from 50 μm to 75 μm.
The thickness of the metal foil is usually from 3 μm to 75 μm, preferably from 5 μm to 30 μm, and more preferably from 10 μm to 25 μm.

Next, the solvent is removed from the liquid crystal polyester composition 30 applied onto the support 12 (FIG. 3B, drying step). The liquid crystal polyester composition from which the solvent has been removed becomes the film precursor 40 that is the subject of the heat treatment. Note that the solvent does not need to be completely removed from the liquid crystal polyester composition; a portion of the solvent contained in the liquid crystal polyester composition may be removed, or all of the solvent may be removed.

The solvent is preferably removed by evaporating the solvent. The temperature at which the solvent is removed is preferably less than the melting point of the liquid crystal polyester, for example, 40°C or higher and 200°C or lower.

The laminate precursor 22 thus obtained, which has the support 12 and the film precursor 40, is heat-treated to obtain the laminate 20, which has the support 12 and the film 10 (the film obtained by heat-treating the film precursor 40) ( FIG. 3C , heat treatment step). At this time, the film 10 formed on the support is obtained.
The heat treatment conditions include, for example, raising the temperature from −50° C., which is the boiling point of the medium, to the heat treatment temperature, and then heat treating at a temperature equal to or higher than the melting point of the liquid crystal polyester.

Like the removal of the solvent, the heat treatment may be carried out continuously or in a sheet-feed manner, but from the standpoint of productivity and operability, it is preferable to carry out the heat treatment in a continuous manner, and it is even more preferable to carry out the heat treatment in a continuous manner following the removal of the solvent.

Next, the film 10 is separated from the laminate 20 having the support 12 and the film 10, thereby obtaining the film 10 as a single layer film (FIG. 3D, separation step). When a metal foil is used as the support, the laminate 20 may be used as a metal-clad laminate for a printed wiring board without separating the film from the laminate 20.

The film manufacturing method of the embodiment makes it possible to produce a film that has excellent adhesion strength with the metal layer and excellent isotropy.

<Laminate>
The laminate of the embodiment includes a metal layer and the film of the embodiment laminated on the metal layer.
2 is a cross-sectional view showing the configuration of a laminate 21 according to one embodiment of the present invention. The laminate 21 includes a metal layer 13 and a film 10 laminated on the metal layer 13.
The film 10 included in the laminate may be the same as that exemplified above, and a description thereof will be omitted.
The metal layer of the laminate may be any of those exemplified as the support in the above-mentioned "Method for producing a film" and the below-mentioned "Method for producing a laminate", and is preferably a metal foil. In terms of electrical conductivity and cost, the metal constituting the metal layer is preferably copper, and the metal foil is preferably copper foil.

The thickness of the laminate in the embodiment is not particularly limited, but is preferably 5 to 130 μm, more preferably 10 to 70 μm, and even more preferably 15 to 60 μm.

The method for producing the laminate of the embodiment is not particularly limited, but the laminate of the embodiment can be produced by the <<Laminate Production Method>> described below.

As one embodiment of the present invention, a laminate can be provided that includes a metal layer and a film formed by applying the liquid crystal polyester composition of the embodiment onto the metal layer.

The laminate of the embodiment can be suitably used for film applications for electronic components such as printed wiring boards.

<<Method for manufacturing laminate>>
The method for producing a laminate of the embodiment includes applying the liquid crystal polyester composition of the embodiment onto a support and forming a film on the support to obtain a laminate including the support and the film. The support may be a metal foil. The laminated metal foil becomes the metal layer.

When the liquid crystal polyester composition contains a solvent, the method for producing the laminate of the embodiment may include applying the liquid crystal polyester composition of the embodiment onto a support, removing the solvent from the liquid crystal polyester composition, and forming a film on the support to obtain a laminate including the support and the film.

The method for producing the laminate of the embodiment may include the following steps.
A step of applying the liquid crystal polyester composition of the embodiment onto a support (application step).
A step of removing the solvent from the applied liquid crystal polyester composition (drying step).

As with the method for producing the film described above, the method for producing the laminate of the embodiment may include a step of heat-treating the liquid crystal polyester composition or the film precursor from which the solvent has been removed (heat treatment step) after the coating step.

The method for producing the laminate of the embodiment may include applying the liquid crystal polyester composition of the embodiment onto a support, removing the solvent from the liquid crystal polyester composition, and heat-treating the composition to form a film on the support, thereby obtaining a laminate including the support and the film. The heat treatment can promote the polymerization reaction of the polymer in the liquid crystal polyester composition and can also promote the volatilization of the solvent.

The heat treatment can also serve as the drying step.
The method for producing the laminate of the embodiment may include applying the liquid crystal polyester composition of the embodiment onto a support, heat treating the composition, and forming a film on the support to obtain a laminate comprising the support and the film.

Figures 3A to 3C are schematic diagrams showing an example of a manufacturing process for the film and laminate of the embodiment. The manufacturing method for the laminate illustrated in Figures 3A to 3C is the same as the manufacturing method described in the manufacturing method for the film described above, except that the separation step (Figure 3D) described above is not performed.

The laminate manufacturing method of the embodiment makes it possible to manufacture a laminate having the film of the embodiment.

The present invention will now be described in more detail with reference to examples, but the present invention is not limited to the following examples.

[Measurement of Flow Initiation Temperature of Liquid Crystal Polyester]
Using a flow tester (Shimadzu Corporation, CFT-500 model), about 2 g of liquid crystal polyester was filled into a cylinder equipped with a die having a nozzle with an inner diameter of 1 mm and a length of 10 mm, and the liquid crystal polyester was melted and extruded from the nozzle while increasing the temperature at a rate of 4°C/min under a load of 9.8 MPa (100 kg/cm ² ), and the temperature (FT) showing a viscosity of 4800 Pa·s (48000 P) was measured.

[Measurement of particle diameter _D50 of liquid crystal polyester particles]
The particle diameter _D50 of the liquid crystal polyester particles was measured using a scattering type particle diameter distribution measuring device (LA-950V2, manufactured by Horiba, Ltd.) The refractive index of pure water was set to 1.333, and the cumulative particle size distribution of the liquid crystal polyester particles on a volume basis was measured, and the particle diameter (μm) at which the cumulative volume ratio was 50% was calculated as the particle diameter _D50 .

[Viscosity Measurement of Polyethersulfone Solution and Liquid Crystal Polyester Solution]
The viscosity was measured using a Brookfield viscometer (TV-22, manufactured by Toki Sangyo Co., Ltd.).
Measurement conditions: sample temperature 23°C, rotor rotation speed 20 rpm

[Peel strength measurement of film with copper foil]
The copper foil-attached film was cut into a 10 mm-wide rectangular shape to prepare three test pieces. For each test piece, with the film held in place, the copper foil was peeled off in a 90° direction to the film at a peeling rate of 50 mm/min using an autograph (AG-1KNIS, manufactured by Shimadzu Corporation) to measure the peel strength (90° peel strength) of the copper foil-attached film, and the average value of the three test pieces was then calculated.

[Production Example of Liquid Crystal Polyester (a) Powder]
Into a reactor equipped with a stirrer, a torque meter, a nitrogen gas inlet tube, a thermometer and a reflux condenser, 940.9 g (5.0 mol) of 6-hydroxy-2-naphthoic acid, 377.9 g (2.5 mol) of 4-hydroxyacetanilide, 415.3 g (2.5 mol) of isophthalic acid and 867.8 g (8.4 mol) of acetic anhydride were placed. After the gas in the reactor was replaced with nitrogen gas, the mixture was heated from room temperature to 140°C over 60 minutes while stirring under a nitrogen gas stream, and refluxed at 140°C for 3 hours. Next, the mixture was heated from 150°C to 300°C over 5 hours while distilling off by-product acetic acid and unreacted acetic anhydride, and then held at 300°C for 30 minutes, after which the contents were removed from the reactor and cooled to room temperature. The obtained solid was pulverized with a pulverizer to obtain a powdered liquid crystal polyester (a1). The flow initiation temperature of this liquid crystal polyester (a1) was 193.3°C.

Liquid crystal polyester (a1) was heated in a nitrogen atmosphere from room temperature to 160°C over 2 hours and 20 minutes, then heated from 160°C to 180°C over 3 hours and 20 minutes, and held at 180°C for 5 hours to polymerize in the solid phase, then cooled and pulverized in a pulverizer to obtain powdered liquid crystal polyester (a2). The flow initiation temperature of this liquid crystal polyester (a2) was 220°C.

Liquid crystal polyester (a2) was heated in a nitrogen atmosphere from room temperature to 180°C over 1 hour 25 minutes, then heated from 180°C to 255°C over 6 hours 40 minutes, and held at 255°C for 5 hours to polymerize in the solid phase, and then cooled to obtain powdered liquid crystal polyester (a). The flow initiation temperature of the liquid crystal polyester (a) powder was 302°C.

[Preparation of Liquid Crystal Polyester Solution (a)]
8 parts by mass of the liquid crystal polyester (a) powder was added to 92 parts by mass of N-methylpyrrolidone (boiling point (1 atm) 204°C) and stirred for 4 hours at 140°C under a nitrogen atmosphere to prepare a liquid crystal polyester solution (a). The viscosity of this liquid crystal polyester solution (a) at 23°C was 955 mPa·s.

[Production Example of Liquid Crystal Polyester (b2) Powder]
Into a reactor equipped with a stirrer, a torque meter, a nitrogen gas inlet tube, a thermometer, and a reflux condenser, 1511.1 g (8.03 mol) of 2-hydroxy-6-naphthoic acid, 410.2 g (2.97 mol) of p-hydroxybenzoic acid, 1291.4 g (12.65 mol) of acetic anhydride, and 0.057 g of 1-methylimidazole were added and stirred at room temperature for 5 minutes, and then the temperature was raised while stirring. When the internal temperature reached 140°C, stirring was continued for 1 hour while maintaining the temperature at 140°C.
Next, the temperature was raised from 140°C to 275°C over 3 hours while distilling off the by-product acetic acid and unreacted acetic anhydride. The contents were taken out after keeping at 275°C for 3 hours and 30 minutes. The taken out contents were cooled to room temperature and pulverized in a pulverizer to obtain a powdered liquid crystal polyester (b1). The flow initiation temperature of this liquid crystal polyester (b1) was 211.8°C.

Liquid crystal polyester (b1) was heated in a nitrogen atmosphere from room temperature to 180°C over 1 hour, then from 180°C to 190°C over 10 minutes, and then from 190°C to 240°C over 8 hours and 20 minutes, and then kept at 240°C for 5 hours to carry out solid-state polymerization. The resulting solid-state polymer was cooled to room temperature to obtain powdered liquid crystal polyester (b2). The flow initiation temperature of this liquid crystal polyester (b2) powder was 266.6°C.

[Production of Liquid Crystal Polyester (b3) Powder]
The liquid crystal polyester (b2) was pulverized using a jet mill (Kurimoto Iron Works'"KJ-200") to obtain a liquid crystal polyester (b3) powder having a particle diameter _D50 of 10 μm.

[Production of polyethersulfone (c1)]
Into a polymerization vessel equipped with a stirrer, a nitrogen inlet tube, a thermometer, and a condenser equipped with a receiver at its tip, bis(4-hydroxyphenyl)sulfone (300.3 g), bis(4-chlorophenyl)sulfone (346.3 g), and diphenylsulfone (570.1 g) as a polymerization solvent were charged, and the temperature was raised to 180° C. while circulating nitrogen gas through the system, to obtain a solution.
To the obtained solution, potassium carbonate (170.8 g) was added, and the temperature was gradually raised to 290° C., and the reaction was allowed to proceed for another 1 hour and 30 minutes at 290° C. The obtained reaction liquid was cooled to room temperature to solidify, and then finely pulverized. After that, the solid was washed several times with hot water and with a mixed solvent of acetone and methanol, and then dried by heating at 150° C., to obtain a polyethersulfone (c1) powder.

[Preparation of polyethersulfone solution (c)]
25 parts by mass of polyethersulfone (c1) powder was added to 75 parts by mass of N-methylpyrrolidone (boiling point (1 atm) 204°C) and stirred at 100°C for 4 hours under a nitrogen atmosphere to prepare a polyethersulfone solution (c). The viscosity of this polyethersulfone solution (c) at 23°C was 3194 mPa·s.

[Production of polyethersulfone (d1)]
Into a polymerization vessel equipped with a stirrer, a nitrogen inlet tube, a thermometer, and a condenser equipped with a receiver at its tip, bis(4-hydroxyphenyl)sulfone (300.3 g), bis(4-chlorophenyl)sulfone (330.8 g), and diphenylsulfone (560.3 g) as a polymerization solvent were charged, and the temperature was raised to 180° C. while circulating nitrogen gas through the system, to obtain a solution.
To the obtained solution, potassium carbonate (159.7 g) was added, and the temperature was gradually raised to 290° C., and the reaction was allowed to proceed for an additional 3 hours at 290° C. The obtained reaction liquid was cooled to room temperature to solidify, and then finely pulverized. After that, the solid was washed several times with warm water and with a mixed solvent of acetone and methanol, and then dried by heating at 150° C. to obtain an aromatic polysulfone (d1) powder.

[Preparation of polyethersulfone solution (d)]
25 parts by mass of polyethersulfone (d1) powder was added to 75 parts by mass of N-methylpyrrolidone (boiling point (1 atm) 204°C) and stirred at 100°C for 4 hours under a nitrogen atmosphere to prepare a polyethersulfone solution (d). The viscosity of this polyethersulfone solution (d) at 23°C was 380 mPa·s.

[Production of Thermoplastic Polyimide (e)]
In a reactor equipped with a stirrer, a Dean-Stark apparatus, and a thermometer, 600 g of 2-(2-methoxyethoxy)ethanol and 218.58 g (1.00 mol) of pyromellitic dianhydride were mixed and stirred at a stirring speed of 150 rpm under nitrogen flow. Separately, 49.42 g (0.347 mol) of 1,3-bis(aminomethyl)cyclohexane, 93.16 g (0.645 mol) of 1,8-octamethylenediamine, and 250 g of 2-(2-methoxyethoxy)ethanol were mixed to obtain a solution. The stirring speed of the reactor was set to 250 rpm, and the solution was gradually dropped into the reactor under nitrogen flow. After the entire solution was dropped, a mixture of 130 g of 2-(2-methoxyethoxy)ethanol and 1.934 g (0.0149 mol) of n-octylamine prepared separately was added, and the mixture was further stirred in the reactor. Next, the stirring speed of the reactor was set to 200 rpm, and the internal temperature of the reactor was raised to 190°C and maintained for 30 minutes. After the temperature of the contents in the reactor was allowed to cool to room temperature, the contents were filtered to obtain a resin. The resin was washed with 300 g of 2-(2-methoxyethoxy)ethanol and 300 g of methanol, filtered, and then dried in a dryer at 180°C for 10 hours. The obtained resin was finely pulverized to obtain a thermoplastic polyimide (e) powder.

[Preparation of Dispersion]
(Examples 1 to 12, Comparative Example 1)
The liquid crystal polyester (b3) powder and any one of the polyethersulfone solution (c), the polyethersulfone solution (d), and the thermoplastic polyimide (e) were added to the liquid crystal polyester solution (a) obtained above so as to obtain the blending amount (parts by mass) of each component shown in Table 1, and a dispersion was prepared using a stirring and degassing device (Keyence Corporation, HM-500). The liquid crystal polyester (b3) powder and the thermoplastic polyimide (e) powder were insoluble in N-methylpyrrolidone.

[Manufacturing of films and laminates]
The dispersions of Examples 1 to 12 and Comparative Example 1 were cast onto the roughened surface of a copper foil (JXEFL-V2, 12 μm thick, manufactured by JX Metals Corporation) using a micrometer-equipped film applicator (SA204, manufactured by Tester Sangyo Co., Ltd.) and an automatic coating device (I-type, manufactured by Tester Sangyo Co., Ltd.) so that the thickness of the cast film was 300 μm. Thereafter, the cast film was dried at 40° C. and normal pressure (1 atm) for 4 hours to partially remove the solvent from the cast film.

The dried copper foil-attached films produced in Examples 1 to 12 and Comparative Example 1 were further heat-treated in a hot air oven under a nitrogen atmosphere by heating from room temperature to 310°C over 4 hours and holding at that temperature for 2 hours. As a result, a heat-treated copper foil-attached film (total thickness of laminate: 42 μm) was obtained. The peel strength of this copper foil-attached film was measured and is shown in Table 1.

The peel strength of the copper foil-attached film obtained from the composition of Comparative Example 1, which contained liquid crystal polyester (a) and liquid crystal polyester (b3), was 4.0 N/cm. In contrast, the copper foil-attached films obtained from the compositions of Examples 1 to 12, which further contained polyethersulfone (c1), polyethersulfone (d1), or thermoplastic resin polyimide (e) in addition to the composition of Comparative Example 1, all had improved adhesion strength with the copper foil (metal layer), measured as peel strength.

The configurations and combinations thereof in each embodiment are merely examples, and modifications such as addition, omission, and substitution of configurations are possible without departing from the spirit of the present invention. Furthermore, the present invention is not limited to each embodiment, but is limited only by the claims.

10...film, 12...support, 13...metal layer, 20, 21...laminate, 22...laminate precursor, 30...liquid crystal polyester composition, 40...film precursor

Claims (14)

A liquid crystal polyester (A),
At least one thermoplastic resin selected from the group consisting of thermoplastic polyimide and aromatic polysulfone;
The liquid crystal polyester composition, wherein the liquid crystal polyester (A) has a repeating unit derived from an aromatic hydroxylamine or a repeating unit derived from an aromatic diamine. The liquid crystal polyester composition according to claim 1, wherein the liquid crystal polyester (A) has a repeating unit represented by the following formula (A1), a repeating unit represented by the following formula (A2), and a repeating unit represented by the following formula (A3).
(A1)-O-Ar ¹ -CO-
(A2) -CO-Ar ² -CO-
(A3)-X-Ar ³ -Y-
(Wherein,
Ar ¹ represents a 1,4-phenylene group, a 2,6-naphthylene group, or a 4,4′-biphenylene group;
^Ar2 represents a 1,4-phenylene group, a 1,3-phenylene group, or a 2,6-naphthylene group;
^Ar3 represents a 1,4-phenylene group or a 1,3-phenylene group;
X represents --NH--, and Y represents --O-- or --NH--.
The hydrogen atoms in the groups represented by Ar ¹ , Ar ² and Ar ³ may each be independently substituted with a halogen atom, an alkyl group or an aryl group. Further, the liquid crystal polyester particles include a liquid crystal polyester (B),
3. The liquid crystal polyester composition according to claim 1, wherein the liquid crystal polyester (B) has no repeating units derived from an aromatic hydroxylamine and no repeating units derived from an aromatic diamine. The liquid crystal polyester composition according to claim 3, wherein the content of the liquid crystal polyester particles is 5% by mass or more and 80% by mass or less with respect to 100% by mass of the total content of solids contained in the liquid crystal polyester composition. The liquid crystal polyester composition according to claim 1 or 2, wherein the content of the thermoplastic resin per 100 parts by mass of the liquid crystal polyester (A) is 1 part by mass or more. The liquid crystal polyester composition according to claim 1 or 2, wherein the content of the liquid crystal polyester (A) in the liquid crystal polyester composition is 10% by mass or more and 90% by mass or less, relative to 100% by mass of the total content of solids contained in the liquid crystal polyester composition. The liquid crystal polyester composition according to claim 1 or 2, further comprising a solvent capable of dissolving the liquid crystal polyester (A). The liquid crystal polyester composition according to claim 1 or 2, wherein the thermoplastic resin is a thermoplastic polyimide. The liquid crystal polyester composition according to claim 8 , wherein the thermoplastic polyimide has a repeating unit represented by the following formula (I) and a repeating unit represented by the following formula (II):

(In the formula, R ₁ is a divalent group having 6 to 22 carbon atoms containing at least one alicyclic hydrocarbon structure. R ₂ is a divalent chain aliphatic group having 5 to 16 carbon atoms. X ₁ and X ₂ are each independently a tetravalent group having 6 to 22 carbon atoms containing at least one aromatic ring.) The liquid crystal polyester composition according to claim 9, wherein the content of the repeating unit of formula (I) is 20 mol% or more and 70 mol% or less with respect to the total 100 mol% of the repeating unit of formula (I) and the repeating unit of formula (II) in the thermoplastic polyimide. A liquid crystal polyester (A),
At least one thermoplastic resin selected from the group consisting of thermoplastic polyimide and aromatic polysulfone;
A liquid crystal polyester composition comprising: a liquid crystal polyester (A) and a solvent capable of dissolving the liquid crystal polyester (A). A liquid crystal polyester (A),
At least one thermoplastic resin selected from the group consisting of thermoplastic polyimide and aromatic polysulfone;
The liquid crystal polyester (A) has a repeating unit derived from an aromatic hydroxylamine or a repeating unit derived from an aromatic diamine. A laminate comprising a metal layer and the film according to claim 12 laminated on the metal layer. A method for producing the laminate according to claim 13, comprising applying the liquid crystal polyester composition according to claim 1, 2 or 11 onto a metal layer and forming a film on the metal layer.

Images